Topic 5.2 Photosynthesis Flashcards
State the word equation for photosynthesis
carbon dioxide + water —> glucose + oxygen
State the symbol equation for photosynthesis
6CO2+ 6H2O —> C6H12O6 + 6O2
What is meant by autotrophic?
organisms make complex organic compounds from simple compounds in their environment
Define photosynthesis
the process by which living organisms, particularly plants and algae, capture the energy from the sun using chlorophyll and use it to convert carbon dioxide and water into simple sugars
What are heterotrophic organisms?
organisms that obtain complex organic molecules by feeding on other living organisms or their dead remains
What is the envelope of a chloroplast?
the outer and inner membranes along with the intermembrane space
What are grana?
stacks of thylakoid membranes within a chloropast
What is a thylakoid?
a membrane disc found in a grana of a chloroplast
What are lamellae?
extensions of the thylakoid membranes which connect 2 or more grana, acting as a support skeleton in the chloroplast, maintaining a working distance between the grana so that they get maximum light and function as efficiently as possible
What is the stroma?
the matrix which surround the grana and contains all the enzymes needed to complete the process of photosynthesis and produce glucose
What is chlorophyll a?
a blue-green photosynthetic pigment, found in all green plants
What is chlorophyll b?
a yellow-green photosynthetic pigment
What are carotenoids?
photosynthetic pigments made up of orange carotene and yellow xanthophyll
What is phaeophytin?
a grey pigment which is a breakdown product of the other photosynthetic pigments
Define photosystem I
a combination of chlorophyll pigments which absorbs light of 700nm wavelength and involved in cyclic and non-cyclic phosphorylation
Define photosystem II
a combination of chlorophyll pigments which absorbs light of 680nm and only involved in non-cyclic phosphorylation
Where are PSIs found?
intergranal lamellae (join the granum together)
Where are PSIIs found?
on the grana
Define absorption spectrum
the range of different wavelengths of light that a photosynthetic pigment absorbs against the wavelength of light (displayed as a graph)
Define action spectrum
the rate of photosynthesis against the wavelength of light absorbed, displayed as a graph
What are the 2 stages of photosynthesis?
- light-dependent
- light-independent
What does the light-dependent consist of?
photolysis and phosphorylation to generate ATP and split water molecules
What are the 2 types of phosphorylation?
cyclic and non-cyclic
What does the light-independent stage consist of?
the Calvin cycle